This invention relates to a storage box apparatus for a motorcycle and positioned at the upper central portion of a body of the motorcycle.
There has been provided a motorcycle provided with a large storage box capable of accommodating a "full-face" helmet at the upper central portion of the motorcycle body.
It is required that such a storage box function as a knee-grip and be comparatively robust. On the other hand, it is also required that the storage box be light in weight and, therefore, in most cases, the storage box is made of synthetic resin material.
Since, however, the appearance of the storage box is also important, it is designed with a substantially stream-surfaced shape including an opening/closing lid, and moreover because of its large size, problems of productivity and costs occur in performing a precise monolithic molding.
Although improvements may be made with respect to these points if the storage box is molded in parts and then welded together, there have been problems that, when trying to achieve a strong unification, a wide bead line of welding remains which mars the appearance and requires considerable processing and labor to remedy.